ID 2913 -
Metionina
PL: Metionina
EN: L-methionine
Pdf: methionine
Oświadczenie (2)
- metabolizmu lipidów
- poprawa jakości białka
- poprawa jakości białka, modulacja metabolizmu lipidów
1. Charakterystyka żywności / składnika
The food constituent that is the subject of the health claims is methionine.
Methionine is an indispensable, sulphur-containing amino acid which plays a role in intermediary metabolism, both as a building block in protein synthesis and as a cofactor in certain metabolic pathways, such as in methyl transfer reactions as part of S-adenosyl methionine (SAM). Methionine occurs naturally in foods, mainly as part of proteins, and is also available in supplement form. Methionine can be measured in foods by established methods.
The Panel considers that the food constituent, methionine, which is the subject of the health claim, is sufficiently characterised.
2. Znaczenie oświadczenia dla zdrowia człowieka
The claimed effects are “lipid metabolism” and “improvement of protein quality, modulation of lipid metabolism”. The Panel assumes that the target population is the general population.
The Panel notes that “improvement of protein quality” relates to a beneficial nutritional property of a food/food constituent rather than to the relationship between a food/food constituent and health as required by Regulation (EC) No 1924/2006.
In the context of the proposed wordings, the Panel assumes that the claimed effect refers to the maintenance of normal blood cholesterol concentrations.
Low-density lipoproteins (LDL) carry cholesterol from the liver to peripheral tissues, including the arteries. Elevated LDL-cholesterol, by convention >160 mg/dL (>4.14 mmol/L), may compromise the normal structure and function of the arteries. High-density lipoproteins (HDL) act as cholesterol scavengers and are involved in the reverse transport of cholesterol in the body (from peripheral tissues back to the liver).
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The Panel considers that maintenance of normal blood cholesterol concentrations is a beneficial physiological effect.
3. Naukowe uzasadnienia wpływu na zdrowie człowieka - Utrzymanie prawidłowego stężenia cholesterolu we krwi
Among the references provided for the scientific substantiation of this claim one refers to the role of methionine in lipid metabolism in rats (Oda, 2006). The other references deal with methionine metabolism and kinetics, methionine requirements and toxicity, and methionine in relation to homocysteine metabolism.
No human data were provided on the effects of methionine intake on blood cholesterol concentrations.
Comparative studies in rats fed cholesterol free diets with different protein sources, i.e. soy versus casein, with and without added methionine, indicated different effects on plasma lipids, i.e. HDL- and VLDL-cholesterol concentrations and transcription of the apo-A-1 gene (Oda, 2006). The Panel considers that results from rat studies cannot be extrapolated to humans because of differences in lipid metabolism between species.
The Panel concludes that a cause and effect relationship has not been established between the dietary intake of methionine and the maintenance of normal blood cholesterol concentrations.
Warunki i możliwe ograniczenia stosowania oświadczenia
Human data generally show an observed safe level of intake as 5 times the daily requirement, but uncertainty factor would have to be applied.
Overweight adults
AMOUNT RECOMMENDATION:: 2 - 5 g methionine per day